Here's the scary thing about diabetes: Over 30 million Americans have it, with an additional 1.4 million new diagnoses each year. The disease is the seventh-highest cause of death in the U.S.

Those are concerning statistics, but there are also some numbers that provide hope. Over 170 new medicines are currently in development targeting treatment of diabetes and diabetes-related conditions. Here are three of the most promising diabetes drugs from five of the most innovative drugmakers in the world: Merck (NYSE:MRK), Pfizer (NYSE:PFE), Lexicon Pharmaceuticals (NASDAQ:LXRX), Sanofi (NASDAQ:SNY), and Novo Nordisk (NYSE:NVO).

Doctor writing "diabetes"

Image source: Getty Images.

1. Ertugliflozin

Merck and Pfizer are collaborating on development of ertugliflozin, an experimental drug for treating patients with type 2 diabetes. The drug could be approved in the U.S. later this year as a stand-alone treatment, in combination with Merck's Januvia, and in combination with metformin.

Ertugliflozin belongs to a class of medicines known as SGLT2 inhibitors. These drugs lower blood sugar by causing the kidneys to remove sugar from the body through the urine. Several SGLT2 inhibitors are already available, including Farxiga, Invokana, and Jardiance. 

Results from late-stage clinical studies conducted by Merck and Pfizer were very encouraging. Not only did ertugliflozin help lower blood sugar levels, but patients taking the experimental drug also experienced weight reduction and lower blood pressure levels. 

2. Sotagliflozin

Another promising SGLT inhibitor might not be too far behind ertugliflozin. Lexicon and Sanofi are evaluating sotagliflozin in late-stage studies. The drug could potentially reach the market within the next couple of years if all goes well.

Sotagliflozin inhibits SGLT1 and SGLT2 proteins. SGLT1 is responsible for glucose absorption in the gastrointestinal tract, while SGLT2 is responsible for glucose reabsorption by the kidney. Lexicon, which originally developed sotagliflozin, is focusing on clinical studies for type 1 diabetes, while Sanofi is handling clinical development and potential commercialization for type 2 diabetes. 

Lexicon reported positive results from the first two late-stage studies of sotagliflozin in treating type 1 diabetes in 2016, with significant reductions in patients' blood sugar levels. The company has one other late-stage study in progress for the indication; results should be available by mid-2017. Sanofi also has three additional clinical trials underway evaluating the drug in treating type 2 diabetes. 

3. Semaglutide

Novo Nordisk hopes to win regulatory approval for its newest diabetes drug, semaglutide, by Dec. 5, 2017. The pharmaceutical company submitted for approval in the U.S. and in Europe late last year.

Semaglutide targets type 2 diabetes by mimicking the action of the glucagon-like peptide-1 (GLP-1) receptor. GLP-1 stimulates the release of insulin and reduces glucagon, a hormone that increases blood sugar levels. If approved, semaglutide would join other GLP-1 receptor agonists such as Trulicity and Victoza. 

Late-stage studies found that semaglutide lowered blood sugar levels and resulted in weight reduction in patients taking the drug. In addition, semaglutide demonstrated reduction in cardiovascular risk compared to placebo. 

Into the future

An even more exciting diabetes treatment could be available in the future. Glucose-responsive insulin (GRI), also known as "smart insulin," holds the potential to detect blood sugar levels and automatically release the correct dosage to adjust those levels.

At least two of the companies already mentioned are developing glucose-responsive insulin products. Merck's MK-2640 is in early-stage testing. Sanofi has partnered with diabetes research group JDRF to develop glucose-responsive insulin. 

It will take several years before these products could be on the market, however. And there's always a risk that issues arise in the clinical-development or regulatory-approval processes. (By the same token, the possibility also exists that ertugliflozin, sotagliflozin, and/or semaglutide could stumble along the way.) However, the chances that diabetes becomes less scary in the future thanks to new treatments appear to be pretty good.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.